The present invention relates to an arrangement, hereafter system, as defined in the preamble of claim 1, to a clamp or pipe clamp with such a system, and to a compression ring or shrink ring comprising such a system.
When clamping tubular elements on a corresponding peripheral zone of a cylindrical structure such as a shaft or another pipe, so-called clamping ring known per se are used.
Such clamping rings fitted with so-called ears are known in practice but inappropriate in some cases. In particular, lack of space may preclude accommodating the ears.
In such instances so-called clamping or compression rings have been found practical: these are externally shrunk-on or compressed, or else they stretch the cylindrical structure to press the two pipes against each other.
Such clamps and compression rings are manufactured by sawing, stamping or cutting annular segments from or out of pipes of appropriate diameters. Such manufacture however incurs drawbacks because:
(a) the newly made pipes must be deburred at the outer longitudinal ring sides, i.e., a further processing stage is required,
(b) only non-oxidizing materials can be used, notxe2x80x94for instancexe2x80x94galvanized pipes, the rings being damaged at the longitudinal sides, in other words galvanizing is lacking there, and
(c) only one ring size can be manufactured from the pipe diameter.
Another manufacturing procedure consists in xe2x80x9cevertingxe2x80x9d the so-called support washers, substantial forces being required and the large inner stresses being present in the ring. Once a ring""s size is given, rings of arbitrary diameters cannot be made.
Another way might be to manufacture a ring from an appropriate strip segment cut out of an endless belt, namely by bending the segment in circular manner. However it was found that the connection of the two ends of the segment are a weak point and in particular cannot withstand tension or butting.
The German patent 40 09 259 discloses a system connecting two terminal strip segment edges in order to make a clamp or a so-called shrink ring which in particular can withstand tensile and compressive stresses. This junction may be improved further in that laser spot welds are used along the junction line of the mutually engaging segments, or by using-swaged segments. Such a junction, disclosed in said German patent 40 09 259, is shown in FIG. 1. However, where comparatively narrow strips, or shrink rings, are involved, especially if made of aluminum, it was found such a junction allows only a small load, i.e. it will rupture at high tension.
Accordingly it is an objective of the present invention and based on a junction of two terminal strip edges as shown in the German patent document 40 09 259 to propose a junction withstanding higher tensile loads. The invention solves this problem by a system defined in claim 1.
The invention proposes that similarly to the case of the German patent 40 09 259, one terminal edge, or one strip segment, shall comprise a roughly tenon-shaped projection, hereafter called the tenon, which runs in the longitudinal strip direction, said tenon engaging a clearance, hereafter called the mortise, in the other strip segment, said tenon running substantially perpendicularly to the first strip segment""s edge, namely in the belt""s longitudinal direction and comprising at least two stubs mutually apart in the direction of the tenon, i.e. in the strip""s longitudinal direction and which, in the direction of the edge, i.e. in the transverse strip direction, each engage around a zone in the other strip segment.
Preferably the tenon comprises at least two stubs spaced apart in the strip""s longitudinal direction engaging around, and at each side of the said tenon, the other belt segment, i.e. resting in the mortise of the other belt segment so as to geometrically interlock with it.
In one embodiment variation, at least some of the stubs laterally projecting from the tenon and engaging around the other strip segment are designed in such a way comprises an offset running oppositely the strip""s longitudinal direction in one strip segment.
Further preferred embodiment variations of the system of the invention are stated in the dependent claims 2 through 12.
The system defined in the invention is especially applicable to manufacturing a clamp, i.e. to connect and to produce a pipe clamp, in particular a so-called clamping ring or a shrink ring.
The invention is illustratively elucidated below in relation to the attached drawings.
FIG. 1 shows a junction of two terminal strip edges disclosed in the German patent 40 09 259, in other words as known from the state of the art,
FIG. 2 shows a system of the invention to join two terminal strip edges,
FIG. 3 shows the system of FIG. 2 in exploded form,
FIG. 4 shows a clamping ring, i.e. a pipe clamp, comprising a system of the invention, in the disconnected, opened state,
FIG. 5 shows the connection of a shaft to a bellows-like pipe, i.e. a flexi-tube, when using a clamp of the invention, namely a compression ring, and
FIGS. 6a, 6b are outlines of a system of the state of the art and of a system of the invention under tensile stress.